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@ -21,7 +21,7 @@ |
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until such time as a tuple is inserted, updated, deleted, or locked on |
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until such time as a tuple is inserted, updated, deleted, or locked on |
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that page. The page-level <literal>PD_ALL_VISIBLE</literal> bit has the |
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that page. The page-level <literal>PD_ALL_VISIBLE</literal> bit has the |
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same meaning as the all-visible bit in the visibility map, but is stored |
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same meaning as the all-visible bit in the visibility map, but is stored |
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within the data page itself rather than a separate data tructure. These |
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within the data page itself rather than a separate data structure. These |
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will normally agree, but the page-level bit can sometimes be set while the |
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will normally agree, but the page-level bit can sometimes be set while the |
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visibility map bit is clear after a crash recovery; or they can disagree |
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visibility map bit is clear after a crash recovery; or they can disagree |
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because of a change which occurs after <literal>pg_visibility</> examines |
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because of a change which occurs after <literal>pg_visibility</> examines |
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